feat: add danmuku plugin documentation and i18n setup guide

- Created a new documentation file for the danmuku plugin, detailing its usage and providing code examples.
- Added a comprehensive guide for language settings (i18n), including instructions for importing languages, setting default languages, and modifying language options.
- Included code snippets for initializing the Artplayer with different languages and examples for adding new languages.

docs/assets/ts/artplayer-plugin-vast.d.ts

@@ -1,20 +1,34 @@
 import type Artplayer from 'artplayer';
+import { Player } from '@glomex/vast-ima-player';
 
 export = artplayerPluginVast;
 export as namespace artplayerPluginVast;
 
-type Option = (params: {
+declare global {
+    interface Window {
+        artplayerPluginVast?: typeof artplayerPluginVast;
+    }
+}
+
+type PlayUrlFn = (url: string) => void;
+type PlayResFn = (res: string) => void;
+
+interface VastPluginContext {
     art: Artplayer;
-    id: string;
-    ima: any;
-    imaPlayer: any;
-    $container: HTMLDivElement;
-    playUrl: (url: string) => void;
-    playRes: (res: string) => void;
-}) => void;
+    ima: typeof google.ima;
+    imaPlayer: Player;
+    playUrl: PlayUrlFn;
+    playRes: PlayResFn;
+    container: HTMLDivElement | null;
+}
 
-type Result = {
+export type ArtplayerPluginVastOption = (params: VastPluginContext) => void | Promise<void>;
+
+export interface ArtplayerPluginVastInstance {
     name: 'artplayerPluginVast';
-};
+    destroy?: () => void;
+}
 
-declare const artplayerPluginVast: (option: Option) => (art: Artplayer) => Result;
+declare function artplayerPluginVast(
+    option: ArtplayerPluginVastOption,
+): (art: Artplayer) => ArtplayerPluginVastInstance;